Troubleshooting MOTU MIDI Express 128 Connectivity in macOS Sonoma

It seems you're facing compatibility issues with the MOTU MIDI Express 128 interface after upgrading to macOS Sonoma. This can be due to various reasons, such as changes in the way the new OS handles certain drivers or USB devices. Here's a guide to help troubleshoot and potentially resolve the issue:

Guide Step by Step:

1. Check MOTU's Official Support: First, visit MOTU's official website or contact their support to check if they have released any updates or patches specifically for macOS Sonoma compatibility.

2. Update Drivers and Software: Ensure you have the latest drivers for the MOTU MIDI Express 128. Sometimes, older drivers may not be fully compatible with newer versions of macOS.

3. Reset MIDI Configuration:

   • Open Audio MIDI Setup (found in Applications > Utilities).
   • Go to the MIDI Studio window (Window > Show MIDI Studio).
   • Remove the MOTU MIDI Express 128 from the list.
   • Reboot your computer and reconnect the device to see if it is recognized correctly.

4. Check USB Port and Cable: Try connecting the device to a different USB port. Also, use a different USB cable to rule out any issues with the cable.

5. IOREG Output Analysis: Given that IOREG reports the device, it indicates that macOS recognizes the hardware. The issue may lie in the MIDI setup or software compatibility.

6. Permissions and Security Settings: With new macOS updates, security and privacy settings can sometimes restrict access to certain devices. Check your System Preferences to ensure that any required permissions are granted.

7. Use Terminal for Further Diagnostics: Use Terminal commands to gather more detailed information about system processes and USB device management. This can help identify if there are any conflicts or errors preventing the device from working properly.

8. Alternative Software Testing: Try using the MIDI Express 128 with different software to rule out specific issues with Logic. For instance, you can test it with another DAW or a MIDI monitor app.

9. Reinstall Ventura on a Separate Partition: If you need the device urgently, consider installing Ventura on a separate partition or external drive. This can help determine if the issue is specifically with Sonoma.

10. Community Forums and Discussions: Search through forums like tonymacx86, MacRumors, or Reddit for discussions about similar issues. Other users with the same hardware may have found workarounds or solutions.

Create config.plist:

In this case, modifying a config.plist file isn’t directly applicable since you're dealing with a real Mac system and not a Hackintosh setup. The config.plist file is specific to Hackintosh systems.

Compatibility issues with audio and MIDI hardware can be quite complex in Hackintosh and even in standard Mac environments, especially after major OS updates. If none of the above steps work, keeping an eye on updates from MOTU and Apple regarding macOS Sonoma compatibility would be advisable.